Paul Delacerda talks about his time at summer camp with the exuberant enthusiasm of a kid just back from a fun-drenched adventure of a lifetime.

But he’s no kid, and this was no Camp Tippecanoe, Kumbaya-singing, sunshine-and-s’mores fest.

No, this was jamming with the likes of Steve Vai and Vince Neil, hammering out a new song with Gene Simmons and hanging out with his camp counselor, who happens to be in Ozzy Osbourne’s band.

This was the very much adults-only Rock and Roll Fantasy Camp, where anyone can discover their inner rock god alongside real-life titans of the music industry.

“The whole thing was freaking unbelievable,” says Delacerda, a former Army paratrooper and Iraq veteran, as well as a lifelong drummer who has dreamed of playing alongside his musical idols. “Are you kidding?! Jamming with Gene Simmons! How do you beat that? It was one of the best things I’ve ever done.”

It’s just one of a growing number of ways grown-ups can reclaim their summers in the name of pure, unadulterated fun.

At www.GrownUpCamps.com, you can find more than 800 camps dedicated to adults-only fun. According to the American Camp Association, the number of accredited camps offering adult programs has increased by nearly 50 percent in the last year.

“Adults go to camps for the same reasons kids do. It’s a way to have fun, get unplugged and learn new things,” says Camp Association CEO Peg Smith. “Maybe we never really grow up.”

She says adult camps typically start at about $500 a week, but can go well over $2,000 a week, depending on location, accommodation and activities.

Adult camps have been around for decades. One of the oldest, for example, offers weekend getaways focused on quilting. The new breed of grown-up camps, however, are often more fitness and adventure-themed, she says.

High Cascade Snowboard Camp, for example, on the slopes of Mt. Hood, Ore., offers seven-day camps for those 21-and-over only, in addition to their more traditional kids’ camps.

In a sign of the times, one adult-only camp in California dubbed “Camp Grounded” sells itself as a “digital detox” where cellphones, laptops and other technology are strictly off-limits.

While digital cameras will get confiscated, old-school film cameras, Polaroids and disposables are acceptable.

“Let’s be clear. This is not a conference, a networking event or meet-up opportunity to make contacts that further your career,” reads the camp website. “Friendships at camp are based on real-life connections, and the most important status we’ll update is our happiness.”

That was true for Delacerda.

“The greatest thing about camp was making friends for life there,” he says. “I still interact on Twitter and Facebook with the people I met.” He has even caught up with some of his rock star counselors when they’ve passed through his hometown on tour.

There’s a clip of him on YouTube playing with Gene Simmons, the Kiss frontman. “You’re good,” Simmons tells Delecerda, who’s grinning ear to ear, as he finishes a riff on the drums. “Do you have a sister? I won’t talk to her, but that was good.”

It’s just one of the memories from camp that Delacerda says he’ll cherish for the rest of his life.

Camp also helped change his life. Building from his experience there, Delacerda built his own band of military brothers in the Houston area, part of a nonprofit music therapy program — dubbed Rock4Recovery — he has created to help other veterans.

“I was just there to rock out and have a good time, but I learned so much that I could pour into what we’re doing here. It was just amazing, I would go back again tomorrow, if I could.”

And of course that’s the great thing about camp: There’s always next summer.